Well you must have either set up a port redirect (ipv4) or opened the port for external traffic (ipv6) yourself. It is not reachable by default as home routers put a NAT between the internet and your devices, or in the case of ipv6 they block any requests. So (unless you have a very exotic and unsafe router) just uhhh don’t 😅 To serve websites it is enough to open 443 for https, and possibly 80 for http if you want to serve an automatic redirect to https.

A colleague of mine had a (non externally reachable) raspberry pi with default credentials being hijacked for a botnet by a infected windows computer in the home network. I guess you’ll always have people come over with their devices you do not know the security condition of. So I’ve started to consider the home network insecure too, and one of the things I want to set up is an internal ssh honeypot with notifications, so that I get informed about devices trying to hijack others. So for this purpose that tool seems a possibilty, hopefully it is possible to set up some monitoring and notification via uptime kuma.